Examination Of The Novel CB/PDMS Electrode For ECG Monitoring Under Chlorine Water

Abstract

While various types of ECG electrodes have been developed for dry conditions and are routinely used in clinical settings, water immersible electrodes for underwater ECG monitoring have not yet been developed. PURPOSE: The purpose of the study was to examine if carbon black powder/Polydimethylsiloxane (CB/ PDMS) electrodes can be utilized in water immersion conditions and to compare their efficacy with some of the commercially-available electrodes. METHODS: Our water-immersible ECG electrode is comprised of a mixture of CB and PDMS. The electrode is low cost, reusable, and has hydrophobic characteristics. In addition, the fabrication procedures can be easily modified and optimized for different applications. Ten participants (28.40±5.91 yrs, 175.0±4.66 cm, and 72.79±11.45 kg) were recruited to examine the electrodes’ performance under chlorinated water. The CB/PDMS electrodes were compared to two commercially-available electrodes (namely, Polar textile and carbon rubber electrodes). The experimental protocols included having the subjects stand while not immersed (dry condition, 2 min) and sit in chlorinated water (immersed condition, 2 min). 30s ECG segments (Lead I configuration) were used for data analysis for each condition and we detected QRS peaks from each ECG cycle. We examined the reduction of QRS peak amplitudes in water immersion when compared to the dry condition. Percentage of ECG amplitude reduction rates with respect to the electrodes’ dry condition were calculated for all compared electrodes in the underwater condition. RESULTS: ECG amplitude reduction rates in immersed condition were 93.81±3.18%, 35.07±40.67%, and 5.36±30.85% for Polar textile, carbon rubber and CB/PDMS electrodes, respectively. Significant amplitude reductions (p<0.05) were found in the immersed condition for Polar textile and carbon rubber electrodes, whereas no significant difference was observed for CB/PDMS when these electrodes were compared against their amplitudes in the dry condition. CONCLUSION: The CB/PDMS electrodes provided near complete hydrophobic characteristics in chlorinated water immersion and are found to be more water resistant than either Polar textile or carbon rubber based electrodes. These electrodes have the potential for monitoring underwater physiological changes.